A relation between the charge radii of π⁺,K⁺,K^(o) derived by the general QCD parametrization

We derive,using the general QCD parametrization,the approximate relation r^{2}(\pi^{+}) - r^{2}(K^(+)) approximately equal to -r^{2}(K^(o), where the r's are the charge radii.The relation is satisfied but the experimental errors are still sizeable.The derivation is similar to (but even simpler than) that for r^{2}(p) -r^{2}(n) approximately equal to r^{2}({\Delta})[Phys.Lett.B 448,107 (1999)].